html{
  font-size: 10px;
  margin: 0;
  padding: 0;
  font-family: serif;
}
.keys{
  display: flex;
  flex: 1;
  flex-wrap: wrap;
  min-height: 100vh;
  align-items: center;
  justify-content: center;
  align-content: center;
}
.keys .key{
  border: 4px solid black;
  border-radius: 5px;
  width: 80px;
  height: 70px;
  margin: 1rem;
  padding: 1rem .5rem;
  text-align: center;
  background: rgba(0,0,0,.7);
  font-size: 1.5rem;
  color: white;
  text-shadow: 0 0 5px black;
  transition: all .07s;
}
.keys .playing{
  transform: scale(1.1);
  border-color: #ffc600;
  box-shadow: 0 0 10px #ffc600;
}
.keys .key kbd{
  font-size: 40px;
  display: block;
  user-select: none;
}
.keys .key .sound{
  font-size: 1.2rem;
  text-transform: uppercase;
  letter-spacing: 1px;
  color: #ffc600;
}